Model Equivalent Circuit Of Antenna Based On UWB Application

Because spectrum regular of Federal Communication Commission (FCC) and emission limits of effective isotropic radiation power (EIRP) limit air interface of impulse signal, and ultra-wideband (UWB) antenna have some different characteristic from narrowband antenna and traditional wideband antenna, engineer should consider co-design of pulse generator circuit and UWB antenna, not just consider UWB antenna or pulse generator circuit lonely. For co-designing pulse generator circuit and UWB antenna in common circuit simulator, it is necessary to model UWB antenna using circuit elements.There are few antenna model methods of equivalent circuit for now, this thesis will consider the disadvantages of some existed antenna model methods and present a system-wide, general, wideband and high precise new antenna model method. Firstly, use electromagnetic simulator software to simulate antenna, and obtain input admittance of the antenna. Secondly, use the rational approximation to fit input admittance curve. Thirdly, deduce the parameters of the rational approximation to RLC lumped-element, then obtain the equivalent circuit model. Lastly, simulate and verify the accurate and precise of the equivalent circuit model in the circuit simulator software.In the thesis, two equivalent circuit models are established by applying this new method: one is equivalent circuit model of linear dipole antenna, whose length is 115mm; the other is equivalent circuit model of transmit/receive antenna and channel. These two methods are all verified on the domain of frequency and time, and good accurate and high precise results are obtained.